Diagnostic tests are used to detect current, active infections of the SARS-CoV-2 virus. Diagnostic tests can be antigen based (“rapid antigen” tests), which look for protein markers on the outside of the virus, or they can be molecular based (including PCR, LAMP, CRISPR), which look for viral genomic material specific to SARS-CoV-2. Molecular based tests that amplify genetic material are also called nucleic acid amplification tests (NAAT). 

More about antigen and molecular tests:

• How do antigen and molecular tests work?
• What is needed to perform an antigen or molecular test?
• How do molecular tests detect SARS-CoV-2?
• Common types of antigen and molecular tests being developed for SARS-CoV-2
• What kind of antigen and molecular tests are on the market? What’s the difference between them?
• Current antigen and molecular tests with FDA EUA Status

For More Information: https://www.centerforhealthsecurity.org/covid-19TestingToolkit/testing-basics/types-of-COVID-19-tests/antigen-and-molecular-tests.html